如何在悬停单元格的WPF DataGridTextColumn上的工具提示中显示多个IDataErrorInfo的错误？

Question

我可以在数据网格中显示一个特定单元格的验证错误，但如果存在

多个目前，我已经在App.xaml包含的一个单独文件中定义了一个样式，作为ResourceDictionary。

风格：

<Style TargetType="{x:Type DataGridRow}">
<Setter Property="FontSize" Value="16"/>
<Setter Property="FontFamily" Value="ArialMT"/>
<Setter Property="Height" Value="24"/>
<Setter Property="VerticalAlignment" Value="Center"/>
<Setter Property="ValidationErrorTemplate">
<Setter.Value>
<ControlTemplate>
<Grid>
<Ellipse Width="12" Height="12" Fill="Red" Stroke="Black" StrokeThickness="0.5"/>
<TextBlock FontWeight="Bold" Padding="4,0,0,0" Margin="0" VerticalAlignment="Top" Foreground="White" Text="!" />
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
<Style.Triggers>
<Trigger Property="Validation.HasError" Value="true">
<!--<DataTrigger Binding="{Binding Path=(Validation.HasError), RelativeSource={RelativeSource AncestorType=DataGridRow}}" Value="true" >-->
<Setter Property="BorderThickness" Value="1"/>
<Setter Property="BorderBrush" Value="Red"/>
<Setter Property="IsEnabled" Value="True" />
<!--<Setter Property="ToolTip" Value="{Binding RelativeSource={x:Static RelativeSource.Self}, Path=(Validation.Errors).Currentitem.ErrorContent}"/>-->
<Setter Property="ToolTip" Value="{Binding RelativeSource={x:Static RelativeSource.Self}, Path=(Validation.Errors)[0].ErrorContent}"/>
</Trigger>
</Style.Triggers>
</Style>
<Style x:Key="cycleErrStyle" TargetType="{x:Type TextBlock}">
<Style.Triggers>
<DataTrigger Binding="{Binding Path=(Validation.HasError), RelativeSource={RelativeSource AncestorType=DataGridRow}}" Value="true" >
<Setter Property="Background" Value="Red" />
<Setter Property="Foreground" Value="White" />
</DataTrigger>
</Style.Triggers>
</Style>

型号类别：

public class RawTag : IDataErrorInfo, INotifyPropertyChanged
{
private readonly int hash;
private string tagName;
private string cycle;
private string source;
public RawTag()
{
hash = GetHashCode();
}
public RawTag(string tagName, string cycle, string source)
{
TagName = tagName;
Cycle = cycle;
Source = source;
hash = GetHashCode();
}
public string TagName
{
get => tagName;
set
{
if (value == tagName) return;
tagName = value;
OnPropertyChanged();
}
}
// should be an integer but any entered value shall be accepted
public string Cycle
{
get => cycle;
set
{
if (value.Equals(cycle))
{
return;
}
cycle = value;
OnPropertyChanged();
}
}
public string Source
{
get => source;
set
{
if (value == source) return;
source = value;
OnPropertyChanged();
}
}
string IDataErrorInfo.Error
{
get
{
StringBuilder error = new StringBuilder();
if (string.IsNullOrEmpty(TagName))
{
error.Append("Name cannot be null or empty");
}
if (!int.TryParse(Cycle.ToString(), out int i))
{
error.Append("Cycle should be an integer value.");
}
return error.ToString();
}
}
string IDataErrorInfo.this[string columnName]
{
get
{
// apply property level validation rules
if (columnName == "TagName")
{
if (string.IsNullOrEmpty(TagName))
return "Name cannot be null or empty";
}
if (columnName == "Cycle")
{
if (!int.TryParse(Cycle.ToString(), out int i))
return "Cycle should be an integer value.";
}
if (columnName == "Source")
{
if (string.IsNullOrEmpty(Source))
return "Source must not be empty";
}
return "";
}
}
public override string ToString()
{
return "TagName: " + TagName + " Cycle: " + Cycle + " Source: " + Source;
}
public bool IsDirty()
{
return hash != GetHashCode();
}
protected bool Equals(RawTag other)
{
return string.Equals(TagName, other.TagName) && string.Equals(Cycle, other.Cycle) && string.Equals(Source, other.Source);
//return string.Equals(TagName, other.TagName) && Cycle == other.Cycle && string.Equals(Source, other.Source);
}
public override bool Equals(object obj)
{
if (ReferenceEquals(null, obj)) return false;
if (ReferenceEquals(this, obj)) return true;
if (obj.GetType() != this.GetType()) return false;
return Equals((RawTag)obj);
}
public override int GetHashCode()
{
unchecked
{
var hashCode = (TagName != null ? TagName.GetHashCode() : 0);
hashCode = (hashCode * 397) ^ (Cycle != null ? Cycle.GetHashCode() : 0);
hashCode = (hashCode * 397) ^ (Source != null ? Source.GetHashCode() : 0);
return hashCode;
}
}
public event PropertyChangedEventHandler PropertyChanged;
[NotifyPropertyChangedInvocator]
protected virtual void OnPropertyChanged([CallerMemberName] string propertyName = null)
{
PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(propertyName));
}
}

我的验证类：

public class CycleValidationRule : ValidationRule
{
public override ValidationResult Validate(object value,
System.Globalization.CultureInfo cultureInfo)
{
BindingGroup group = (BindingGroup)value;
StringBuilder error = null;
foreach (var item in group.Items)
{
IDataErrorInfo info = item as IDataErrorInfo;
if (info != null)
{
if (!string.IsNullOrEmpty(info.Error))
{
if (error == null)
{
error = new StringBuilder();
}
error.Append((error.Length != 0 ? ", " : "") + info.Error);
}
}
}
if (error != null)
return new ValidationResult(false, error.ToString());
else
return new ValidationResult(true, "");
}
}

验证后，我希望故障单元格高亮显示，当悬停故障单元格时，只有该特定单元格/字段的验证错误的错误消息才会显示在工具提示中。

更新2019-01-17:

必须有一种方法将IDataErrorInfo和ValidationRules组合起来，使来自IDataErrorInfo的错误消息进入ValidationRule(目前运行良好)，在那里我可以将错误消息与来自ValidationRule的错误消息组合起来，并向GUI(WPF)提出错误消息的总和。。。但只有来自CCD_ 6的错误消息显示在工具提示中。

Answer 1

IDataErrorInfo不支持每个属性出现多个验证错误。.NET Framework 4.5中引入的更新的INotifyDataErrorInfo接口确实如此。

这里有一个如何实现它的例子。

您可以使用ItemsControl来显示错误消息。举个例子，请看我的答案。